SERIES 2500 SPECIAL STRUCTURES - Standards for …

1 Amendment - May 2001 MANUAL OF CONTRACT DOCUMENTS FOR HIGHWAY WORKSVOLUME 1 SPECIFICATION FOR HIGHWAY WORKSSERIES 2500 SPECIAL STRUCTURESC ontentsClauseTitlePage2501 corrugated Steel BuriedStructures22502 Reinforced Soil and AnchoredEarth Structures32503 Reinforced Clay BrickworkRetaining Walls of Pocket-typeand Grouted-CavityConstruction42504 Environmental Barriers62505(05/01) Drainage Structures82506(05/01) buried Rigid Pipes forDrainage Structures91 Volume 1 Specification for Highway WorksSeries 2500 SPECIAL StructuresSPECIAL STRUCTURES22501 corrugated Steel buried StructuresGeneral1 corrugated steel buried STRUCTURES of clear span orinternal diameter exceeding 900 mm shall comply withthis (11/03) The Contractor shall design the corrugatedsteel buried STRUCTURES listed in Appendix 1/10 inaccordance with Standard BD 12 (DMRB )

2 And thedesign requirements given in Appendix 25 shall comply with SERIES Components4 All helically wound systems and all boltedsegmental systems to be incorporated in the Works shallhave a current Type Approval Certificate. All theindividual components and materials making up thesystem shall comply with the properties listed in thecurrent Type Approval wound systems shall additionally have acurrent British Board of Agr ment Roads and lockseams of helically wound systems shall beable to withstand tensile forces across the seam,according to steel sheet thickness, as tabulated below:Nominal SheetMinimum Tensile ForceThicknessacross Seam(mm)(kN/m) intermediate sheet thicknesses, the minimum tensileforce required may be determined by forming, the depth of the corrugations shallbe within a tolerance of 6% and the pitch of thecorrugations within a tolerance of 4% of the nominaldimensions.

3 Plates shall have a minimum lip of 45 mmbeyond each end crest. Cut edges shall be free fromnotches, gouges, rust or all the plates of a bolted segmental structurehave been assembled, the nuts shall be tightened byapplying a torque within the range stated on the TypeApproval Certificate. The tightening shall be repeated ifnecessary to achieve the required , nuts and washers (if provided) shall be of such adesign that no damage is caused to metal coatings whenthe nuts are tightened as described Dip Galvanizing of Steel Components9(05/01) All surfaces of steel components shall be hotdip galvanized in compliance with the Standards listedin the appropriate Type Approval Certificate and BritishBoard of Agr ment Roads and Bridges for bolted segmental STRUCTURES shall begalvanized after forming the corrugations andcompleting all necessary cutting, punching and in which the galvanized coating has been burnedby welding or otherwise damaged in fabrication,transport.

4 Cutting or handling at site shall be made goodin compliance with Clauses 1907 and and nuts shall be hot dip galvanized incompliance with the Standards listed in the appropriateType Approval Certificate and British Board ofAgr ment Roads and Bridges Foundations of Arch Profile Structures11 Concrete foundations shall be constructed asdescribed in Appendix 25/1 with concrete complyingwith SERIES Invert Pavings12(11/03) Where described in Appendix 25/1, concreteinvert pavings shall be constructed in compliance withthat Appendix using strength class C25/30 concrete anda maximum aggregate size of 20mm complying withSeries invert pavings shall be reinforced with asteel fabric complying with SERIES 1700 having meshdimensions not greater than 150 mm x 300 mm and anominal wire size not less than 5 mm.

5 All laps in themesh shall be at least 150 mm. The steel fabric shall besecurely fixed to the structure by means of fixings at thebolt positions. It shall extend to within a distance notgreater than 100 mm, nor less than 40 mm inside theAmendment - November 2003 Volume 1 Specification for Highway WorksSeries 2500 SPECIAL Structures3edges of the concrete on each side. A nominal cover of45 mm shall be provided to all other faces, includingthat to the crest of the corrugations in the invert pavings shall be cast in lengths notexceeding 10 metres with the provision of a water barbetween adjacent panels and the joints sealed with ajoint sealant to Clause each end of the structure the concrete invertpaving shall be either:(i)(11/03) terminated with a toe that returns atleast 200 mm under the structural steelforming the structure .

6 The steel fabric shallbe folded under the lips of the structure tosuit. The toe shall be detailed with athickness of not less than that required forthe paving, in Standard BD 12(DMRB ); or(ii)detailed to suit any headwall arrangement egpaving reinforcement lapped with foreign matter, (but not any secondaryproprietary protective coating unless indicatedotherwise in the Type Approval Certificate or BritishBoard of Agr ment Roads and Bridges Certificatereferred to in sub-Clauses 4 and 5 of this Clause) andfree standing water shall be removed from the steelsurfaces to be paved, before commencing Invert Pavings17 Any proposed proprietary invert paving systemshall have a current British Board of Agr ment Roadsand Bridges Secondary Protective Coatings AppliedAbove Hot Dip Galvanized Coating18 Any proposed proprietary protective coatingsystem shall have a current British Board of Agr mentRoads and Bridges Protective Coatings19 Where described in Appendix 25/1, exposedgalvanized steel surfaces shall be prepared andprotected after erection in compliance with thatAppendix.

7 The additional protective coating may befactory or site applied and shall have a service life of atleast six years in aggressive Reinforced Soil and Anchored EarthStructuresGeneral1(11/03) Reinforced soil or anchored earth structuresshall comply with this Contractor shall design the reinforced soil oranchored earth STRUCTURES listed in Appendix 1/10 inaccordance with Standard BD 70 (DMRB ) and thedesign requirements and procedures described inAppendix 25 for reinforced soil and anchored earthstructures shall comply with SERIES Elements for Reinforced Soil andAnchor Elements for Anchored Earth3(11/05) Carbon steel strip to be hot dip galvanizedshall comply with BS EN 10025-1 and BS EN 10025-2either grade S235 JR or S355 JR or BS 1449.

8 Part ,either quality KHR 34/20P or quality KHR 50/35P, eachhaving a silicon content of not less than and notmore than The fabricated element shall be hotdip galvanized in compliance with Clause 1909 exceptthat the average zinc coating weight for any individualtest area shall be not less than 1000 g/m .4 Stainless steel strip shall comply with:(i)(11/03) BS EN 10029, BS EN 10048,BS EN 10051, BS EN 10258, BS EN 10259designation or except that thematerial shall be cold rolled to provide proof stress of not less than 400 N/mm and the tensile strength shall be not lessthan 540 N/mm ; or(ii)(11/03) BS EN 10029, BS EN 10048,BS EN 10051, BS EN 10258, BS EN 10259designation CR temper rolled to aminimum proof stress of 310 N/mm.

9 5 Proprietary reinforcing elements and systems usingsuch elements shall have a current British Board ofAgr ment Roads and Bridges (11/06) Anchor elements for anchored earth shall bemade of cold worked steel reinforcing bar conformingto BS EN 10080 and BS 4449 (Grade B500B) exceptthat no bar shall contain a flash weld. Welding of steelreinforcement bars to form anchors shall comply withClause 1717. The fabricated elements shall be hot dipgalvanized in compliance with Clause 1909 except thatthe average zinc coating weight for any individual testarea shall be not less than 1000 g/m .Amendment - November 2006 Volume 1 Specification for Highway WorksSeries 2500 SPECIAL Structures47 Reinforcing and anchor elements shall beprefabricated and delivered to Site ready for installationinto the Works.

10 The elements shall be:(i)Loaded, unloaded and handled in such amanner that:(a) no permanent set or other structuraldamage is caused;(b) the1 protective coating is not damaged.(ii)Stored flat and clearly marked to identifyitems having different lengths and cross-sectional (05/06) Bolts, screws and nuts complying withBS EN ISO 898-1, property classes A and B, shallcomply with BS EN ISO 4014, BS EN ISO 4017 andBS EN ISO 4032, and shall be made from one of thefollowing:(i)(05/06) Steel property class , complyingwith BS EN ISO 898-1 and hot dipgalvanized in compliance with SERIES 1900.(ii)(11/03) Stainless steel to BS EN 10088-1,designation or except that proof stress of the bolt shall be not lessthan 450 N/mm and the tensile strengthshall be not less than 700 N/mm.